APA (7th ed.) Citation

Pius XI, P. (1930). The Soviet Campaign Against God: The Protest of Pope Pius XI. London.

Chicago Style (17th ed.) Citation

Pius XI, Pope. The Soviet Campaign Against God: The Protest of Pope Pius XI. London, 1930.

MLA (8th ed.) Citation

Pius XI, Pope. The Soviet Campaign Against God: The Protest of Pope Pius XI. London, 1930.

Warning: These citations may not always be 100% accurate.